iPhone is RAM constrained

I'd forgotten how RAM constrained the iPhone is:

Daring Fireball: In the Background

... The iPhone (and iPod Touch) only have 128 MB of RAM, and WebKit can use a lot of memory. When memory gets tight, the system sends low memory warnings to running applications, telling them to purge what they can. Eventually, the system will start forcing apps to quit in order to free more memory. That’s why sometimes when you relaunch Safari, it remembers the URLs, but has to reload the content for all of your open web pages — that’s what happens when Safari is asked to quit while it’s running in the background....

I hope the next iteration gives us at least 256MB of RAM. It seems Safari always has to reload my pages. I don't know why...